Lifetime Citizen Portal Access — AI Briefings, Alerts & Unlimited Follows
Labs and private sector outline sampling, moisture correction and validation approaches for hemp testing
Loading...
Summary
Private labs and the DEA described practical lab procedures: moisture‑content correction to report dry‑weight THC, statistical sampling guidelines for large shipments, matrix‑specific method development for oils/edibles/vapes, ISO/DEA registration and the need for validated reference materials.
On an RTI webinar about hemp, industry and DEA speakers described how laboratories handle the technical work of distinguishing hemp from marijuana and how they validate and document methods for customers and courts.
Mike Goodrich, owner of Cornerstone Analytical Laboratories, said most laboratories apply a moisture correction (loss‑on‑drying or moisture balance) to report THC on a dry‑weight basis rather than drying the exact test portion (which can alter terpenes or decarboxylate). Goodrich also described practical sampling and preparation techniques—using liquid nitrogen to freeze and homogenize plant material, reducing particle size and using replicate extracts for method development and precision checks.
For large populations (for example, packages seized in transport), Dr. Sandra Rodriguez Cruz said field agents follow statistical sampling (hypergeometric sampling) incorporated in the DEA agents’ manual: test all packages if fewer than 10; use statistical selection for larger lots. Labs then apply the analytical scheme to selected units.
On validation, Goodrich said private labs use USP/ISO guidelines for accuracy, reproducibility and precision, bracketing runs with standards and control charts; DEA described an uncertainty budget covering accuracy (recovery), reproducibility (heterogeneity) and reference material uncertainty for reported purities.
On accreditation and registration, panelists clarified the difference: laboratories are accredited by third‑party accreditation bodies (e.g., ISO/IEC 17025) while DEA registration permits handling controlled substances under USDA rules. Both accreditation and documented validation increase regulatory burden but improve reliability.
What happens next: labs without quantified reference materials are advised to obtain characterized reference materials and collaborate with DEA and other jurisdictions for verification and training.
